That’s because they can be made into any type of cell that’s needed – they’re essentially the plasticine of the cell world. The problem that scientists have encountered is the difficulty in growing them. For one thing, it’s hard to grow enough of them to perform large-scale experiments. For another, most of the materials upon which the stem cells are grown contain cells or proteins from mouse embryos, which stimulate cell growth but would probably also cause an immune reaction if injected into a human recipient. Researchers from MIT, however, have just announced the creation of a new growing surface that does away with both of these limitations.

The new surface is synthetic, contains no foreign animal material, and lets stem cells stay alive and reproduce themselves into the millions, for at least three months. It’s also the first such material that allows single cells to form colonies of identical cells, which is necessary for identifying cells with desired traits, and has been difficult to achieve with traditional materials.